Screw-set packer



Nov. 8, 1966 c. c. BROWN 3,283,821

SCREW-SET PAGKER Filed Dec. 5, 1963 2 Sheets-Sheet 1 CICERO c BEOWN TOR.7/ INVEN Nov. 8, 1966 c. 0. BROWN SCREW-SET PACKER 2 Sheets-Sheet 2Filed Dec. 5, 1963 C/CEFO C. BROWN I N V EN TOR By uyeaz i A TTO A/EYSUnited States Patent 3,283,821 SCREW-SET PACKER Cicero C. Brown, 8490Katy Road, Houston, Tex. Filed Dec. 5, 1963, Ser. No. 328,282 Claims.(Cl. 166-134) The present invention is directed to a well packerassembly in which an inner-mandrel is locked within a cam actuatedanchoring device and an outer sleeve which is threaded to the innermandrel is rotated therearound to set a flexible packing and anchoringassembly positioned between the lower end of the inner tubular supportand the lower end of the sleeve. Thus the present invention is directedto a screw set well packer assembly.

An object of the present invention is to provide an improved well packerassembly of simple and inexpensive structure which may be employed as ascrew set packer by the rotation of one member around another member inthreaded engagement therewith to compress the flexible packing andanchoring assembly.

Another object of the invention is to provide an improved well packerassembly including a flexible packing and anchoring assembly havingupper and lower seal end rings, a resilient expander wedge and upper'andlower slip members positioned between the respective seal end rings andthe expander wedge whereby movement of one of said seal end rings towardthe other compresses the resilient expander wedge and engages the slipmembers with the well casing to set the well packer assembly.

A further object of the present invention is to provide a screw set wellpacker assembly having greatly reduced friction when being run throughthe well bore than previous devices.

Another object of the present invention is to provide a flexible packingand anchoring assembly in a well packer assembly and includingcup-shaped seal collars which will retain differential pressures fromabove and below when such well packer assembly has been set.

A further object of the present invention is to provide a well packerassembly which when set in a well bore is readily released and retrievedfrom the well bore.

Still another object of the present invention is to provide a wellpacker assembly which may be lowered within a well bore on a tubingstring and set Within the bore and the tubing string removed therefromsubsequent to the setting of the well packer assembly,

These and other objects of the present invention are hereinafter morefully described and explained.

The invention will be more readily understood from reading of thefollowing specification and by reference to the accompanying drawingsfroming a part thereof wherein an example of the invention is shown andwherein:

FIGURE 1 is a View, partly in section and partly in elevation, of a wellpacker assembly constructed in accordance with the invention and showingthe assembly in a normal or unset position.

FIGURE 2 is a similar view with the assembly in its set position withina well bore.

FIGURE 3 is a similar view with the well packer in its set positionwithin the well bore and with the J-body and tubing string removedtherefrom.

FIGURE 4 is a horizontal cross-sectional view taken along lines 4--4 inFIGURE 1.

FIGURE S is a horizontal cross-sectional view taken along line 5-5 inFIGURE 2.

FIGURE 6 is a horizontal cross-sectional View taken along line 66 inFIGURE 2.

In the drawings (FIGURES 1 and 2) the Well packer assembly of thepresent invention is run into a well bore within the well casing Csuspended from the well tubing string T. The well packer assemblyincludes tubular support 10 which has lower external abutment 11 securedto "ice its lower end in supporting relation to the lower end of thegripping unit A and tubular support 10 is threadedly engaged to theinterior of sleeve 12 at its upper end, with flexible packing andanchoring assembly P being positioned around tubular support 10 betweenslip ring 12a which abuts the lower end of sleeve 12 and the upper endof gripping unit A.

J-body 13 is externally threaded onto tubing T and engages pins 14within J-slots 15 which are formed in J- body 13. Pins 14 as best shownin FIGURE 6 are integral with sleeve 12.

Section T1 of tubing string T extends through tubular support 10 and isthreaded at its upper end into J-body 13 and is provided with a suitableseal 16 around its exterior to seal against the interior of tubularsupport 10.

Flexible packing and anchoring assembly P includes upper and lower sealend rings 17 and 18, upper and lower slip members 19 and 20 mountedintegrally with resilient seal collars 21 and 22, respectively.Preferably, slip members 19 and 20 are bonded to seal collars 21 and 22,respectively. With flexible packing and anchoring assembly P in itsunset position as shown in FIGURE 1 the inner surfaces 21a and 22a ofseal members 21 and 22 engage the inclined surfaces 23a and 23b ofexpander wedge 23 on only a small portion of their length. Upper sealend ring 17 is secured to tubular support 10 by shear pin 17b and hasits lower surface 17a in engagement with the upper portion of upper slipmember 19 and upper seal collar 21. Surface 17a of ring 17 as showninclines upwardly and outwardly and mates with similarly inclinedsurfaces 19a on upper slip member 19 and 21b on upper seal collar 21.Lower seal end ring 18 has downwardly and outwardly inclined surface 18ain engagement with similarly inclined surfaces 20a on lower slip memberand surface 2211 on lower seal collar. Lower seal end ring 18 issuitably grooved on its interior surface and is supported on snap ring24 which is positioned in groove 25 in tubular support 10.

The gripping unit A surrounds the lower portion of tubular support :10.External abutment 1.1 is mounted thereon by snap ring 11a in groove 11bin the lower portion of tubular support 10. External abutment 111 isspaced from seal end ring 18 to provide for the mounting of grip-pingelements S of said gripping unit A around tubular support 10.

As shown in FIGURES 4 and 5, each gripping element S is in the form of agenerally semicircular or arcua-te shoe which substantially encirclesone-half of tubular support 10. The lower end of each shoe has adepending extension 26 (FIGURE 1) which coacts with an upstandingprojection 27 on lower abutment 11 while the upper end of each shoe hasan upward extension 28 coaeting with a depending projection 29 for-medon lower seal end ring 18. The coaction between the extensions andprojections limits the outward movement of each shoe with respect totubular support 10.

Each arcuate shoe has an enlarged contact section 30 and the centralouter surface 36a of this section is substantially smooth to engage theWall of the well casing C when the shoe is in non-gripping position.Gripping teeth 3% and 30c are formed on each side of the smooth surfaceStla as is clearly shown in FIGURES 4 and 5. The shoes S are positionedamound tubular support 10 within the space between lower abutment 111and lower sea'l end ring 18 and are urged outwardly under the influenceof coil springs 31 so that their respective smooth surfaces 30a engagethe Wall of the well casing. The ends of the springs 31 are confinedwithin suitable recesses 32 provided in the free ends of the shoes S andsaid springs 31 are relatively weak, being only suflicient to urge thesmooth areas of the shoes into contact with the wall 3 of the pipe witha relatively light friction. This frictional force need be onlysufficient to prevent the .shoe elements from rotating, whereby theassembly may be lowered downwardly through the well casing withoutpresenting any great resistance to such movement.

For the purpose of increasing the engagement of each shoe S with thewall of the casing in order to assure that the tubular support and sealend ring 18 will be held against movement when the assembly is to beset, each gripping shoe S has the internal surface of its enlargedportion 31) inclined in :the manner indicated at 33 and 34. Theseinclined surfaces are adapted to coact with a cam type projection 35which is formed on the external surface of tubular support 111. Asclearly shown in FIG- URE 4, two diametrically opposed projections 35are provided and these projections are normally located as shown in thisfigure with respect to inclined surfaces 33 and 34 of the arcuate shoes.

Upon rotation of the tubular support 10 and its projections 35 withrespect to the shoes S, the projections 35, coacting with one or theother surfaces 33 or 34 of each shoe, will result in imparting a rockingmotion to the shoes :in the manner illustrated in FIGURE 5. Suchmovement of the shoes results in the engagement of gripping teeth 3% or30c of each shoe against the wall of the casing to firmly lock thegripping unit A against rotation or other movement within the wellcasing. Since gripping unit A is carried on tubular support 10 andsupports lower seal end ring 18 the setting of gripping unit A willallow packing and anchoring assembly P to be set as hereinafter morefully explained.

In operation the well packer of the present invention will be run intothe well bore and when it reaches the desired level within casing C, itwill be substantially as shown in FIGURE 1. Setting of the packer isaccomplished by rotating the tubing T to the right where-by J- slot .15engages pin 14 causing sleeve 12 to rotate. Rotation of sleeve 12 willinitially cause rotation of tubular support 10 until projection 35 ontubular support 10 has engaged inclined surfaces 34 of the shoes S andthereby set the shoes. Further rotation of the tubing T will causesleeve 12 to rotate about tubular support 11 and because of the threadedengagement therewith will move sleeve :12 downwardly with respect totubular support 111. This downward :movement will cause shear pin 17b toshear between the inner surface of upper seal end ring 17 and the outersurface of tubular support 10. Further rotation of tubing T will movesleeve 12 downwardly around tubular support 10 forcing upper seal endring 17 downwardly and causing upper slip member 19 and upper sealcollar 21 to move downward-1y over expander sleeve 23. As upper seal endring 17 is moved down toward lower seal end ring 18, the inclinedsurfaces 17a and 18a of rings 17 and 18 will force slip member 19 and2t) and seal collars 21 and 22 outwardly. Further movement will alsocause expander sleeve 23 to move downwardly under lower seal collar 22and lower slip 20. As sleeve 12 moves further down on tubular support1t), inclined surface 22a of seal collar 22 will move outwardly oninclined surface 23b of expander sleeve 23 and inclined surface 21a ofupper seal collar 21 will move outwardly on the inclined surface 23a ofexpander sleeve 23 until upper and lower slips 19 and are in firmengagement with the interior wall of casing C and upper and lower sealcollars 21 and 22 are sealed against the interior of casing C betweenupper and lower slips 19 and 20 as is clearly shown in FIGURE 2. In thisposition flexible packing and anchoring assembly P has been set. Ifdesired 'l-body 13 may be removed from around sleeve 12 and J-body 13and tubing string T completely removed from the well bore as shown inFIGURE 3. In this position the well packer assembly is firmly secured inposition against the interior of casing C both by packing and anchoringassembly P and by gripping unit A,

In order to remove the well packer assembly from the well bore it isnecessary to engage J-body 13 over sleeve 12 wherein pin 14 ispositioned within J-slot 15 as shown in FIGURE 2.. In this position witha slight lift on tubing T pin 14 will be positioned in the lower closedportion of l-slot 15 and may be rotated to the left whereby sleeve 12will be rotated to the left. This rotation may initially unsetprojection 35 from inclined surfaces 34 of gripping unit A if thefriction in the threads between tubular support 10 and sleeve 12 exceedsthe friction between projections 35 and surfaces 34-. Continued rotationwill rotate tubular support 10 and projection 35 will then catch theopposite inclined surfaces 33 causing engagement of the teeth 30b in thewall of casing C, thus resetting gripping unit A. Further rotation ofthe tubing will cause sleeve 12 to rotate about tubular support 10 andmove upwardly the threaded connection therebetween. The upward movementof sleeve 12 will allow seal collars 21 and 22 and expander sleeve 23 toretract and to return to their normal shape. As sleeve 12 continues itsupward rotation the resiliency of seal collars 21 and 22 and expandersleeve 23 will cause slips 19 and 22 to disengage from the interiorcasing C and return to their retracted position as shown in FIG- URE 1.With packing and anchoring assembly P thus unseated, it is onlynecessary to rotate tubing T slightly to the right to disengageprojection 35 from inclined surface 33 thereby releasing gripping unit Aand the well packer assembly may be pulled from the well bore. Pin 36extends through sleeve 12 as shown and projects into the space aroundtubular support 11 below the threads on the upper exterior of tubularsupport 10. Pin 36 will thus provide a stop for the upward movement ofsleeve 12 to prevent sleeve 12 from completely disengaging from tubularsupport 10.

The foregoing disclosure and description of the invention isillustrative and explanatory thereof and the various changes in size,shape and materials, as well as in the details of the illustratedconstruction, may be made within the scope of the appended claimswithout departing from the spirit of the invention.

What is claimed is:

1. A releasable well packer assembly adapted to be lowered on a tubingstring and set in a well bore, comprising a tubular support having anexternal abutment near its lower end,

a sleeve surrounding and threadedly engaging the upper end of saidtubular support so that relative rotation between said sleeve and saidtubular support moves said sleeve longitudinally on said tubularsupport,

means mounted on said tubular support and engaging the wall of the wellbore to restrain said tubular support against rotation,

a sealing and anchoring assembly mounted around said tubular supportbetween said abutment and said sleeve,

said assembly including a resilient expander wedge having upper andlower conical surfaces which diverge outward toward each other,resilient sealing means associated with said wedge so that both saidwedge and said sealing means are simultaneously deformed radiallyoutward in engagement with the Wall of the well bore upon theapplication of an endwise force thereto and on release of said force toreturn to their undeformed position, and upper and lower slip membersassociated with said sealing means and movable outward therewith intopipegripping position with the wall of the well bore when said sealingmeans is deformed outward,

said restraining means holding said tubular support stationary so thatsaid sleeve may be rotated relative to said tubular support,

such relative rotation in one direction moving said sleeve downward onsaid tubular support to apply an endwise force against said sealing andanchoring assembly to set the same, and such relative rotation in theopposite direction moving said sleeve upward on said tubular support toremove the endwise force against said sealing and anchoring assembly torelease the same. 2. A releasable well packer according to claim 1,including 1111621118 releasably securing said sealing and anchoringassembly to said tubular support and engageable by the sleeve when saidsleeve is moved downward on the support, whereby said means is released.3. A releasable well packer assembly according to claim 1, includingmeans on said sleeve for connection with said tubing string whereby thewell packer may be lowered into a well bore and actuated by manipulationof said tubing string at the surface of the well bore. 4. A releasablewell packer according to claim 3, wherein said tubing string extendsdownwardly through said well packer assembly within said tubularsupport, and sealing means between the exterior of said tubing stringand the interior of said tubular support completing the sealing betweenthe exterior of the tubing string and the wall of the well bore whensaid well packer assembly is set. 5. A releasable well packer assemblyaccording to claim 1, wherein said restraining means includes at leasttwo gripping members mounted on said tubular support and havingoutwardly projecting gripping surfaces,

means normally holding said gripping surfaces out of gripping engagementwith the wall of the well bore, and

means on said tubular support moving said gripping surfaces intogripping engagement with the wall of the well bore responsive to apartial rotation of the tubular support to restrain said tubular supportagainst further rotation and releasing said gripping surfaces fromengagement with the wall of the well bore responsive to a rotation ofsaid tubular support in the opposite direction from the direction ofrotation moving said gripping surfaces into gripping engagement.

References Cited by the Examiner UNITED STATES PATENTS 1,303,091 4/1919Mack 166-139 3,066,738 12/1962 Myers 166134 3,096,824 7/1963 Brown166-138 3,181,614 5/1965 Brown 166134 CHARLES E. OCONNELL, PrimaryExaminer.

JACOB L. NACKENOFF, Examiner.

J. A. LEPPINK, Assistant Examiner.

1. A RELEASABLE WELL PACKER ASSEMBLY ADAPTED TO BE LOWERED ON A TUBINGSTRING AND SET IN A WELL BORE, COMPRISING A TUBULAR SUPPORT HAVING ANEXTERNAL ABUTMENT NEAR ITS LOWER END, A SLEEVE SURROUNDING ANDTHREADEDLY ENGAGING THE UPPER END OF SAID TUBULAR SUPPORT SO THATRELATIVE ROTATION BETWEEN SAID SLEEVE AND SAID TUBULAR SUPPORT MOVESSAID SLEEVE LONGITUDINALLY ON SAID TUBULAR SUPPORT, MEANS MOUNTED ONSAID TUBULAR SUPPORT AND ENGAGING THE WALL OF THE WELL BORE TO RESTRAINSAID TUBULAR SUPPORT AGAINST ROTATION, A SEALING AND ANCHORING ASSEMBLYMOUNTED AROUND SAID TUBULAR SUPPORT BETWEEN SAID ABUTMENT AND SAIDSLEEVE, SAID ASSEMBLY INCLUDING A RESILIENT EXPANDER WEDGE HAVING UPPERAND LOWER CONICAL SURFACES WHICH DIVERGE OUTWARD TOWARD EACH OTHER,RESILIENT SEALING MEANS ASSOCIATED WITH SAID WEDGE SO THAT BOTH SAIDWEDGE AND SAID SEALING MEANS ARE SIMULTANEOUSLY DEFORMED RADIALLYOUTWARD IN ENGAGEMENT WITH THE WALL OF THE WELL BORE UPON THEAPPLICATION OF AN ENDWISE FORCE THERETO AND ON RELEASE OF SAID FORCE TORETURN TO THEIR UNDERFROMED POSITION, AND UPPER AND LOWER SLIP MEMBERSASSOCIATED WITH SAID SEALING MEANS AND MOVABLE OUTWARD THEREWITH INTOPIPEGRIPPING POSITION WITH THE WALL OF THE WELL BORE WHEN SAID SEALINGMEANS IN DEFORMED OUTWARD, SAID RESTRAINING MEANS HOLDING SAID TUBULARSUPPORT STATIONARY SO THAT SAID SLEEVE MAY BE ROTATED RELATIVE TO SAIDTUBULAR SUPPORT, SUCH RELATIVE ROTATION IN ONE DIRECTION MOVING SAIDSLEEVE DOWNWARD ON SAID TUBULAR SUPPORT TO APPLY AN ENDWISE FORCEAGAINST SAID SEALING AND ANCHORING ASSEMBLY TO SET THE SAME, AND SUCHRELATIVE ROTATION IN THE OPPOSITE DIRECTION MOVING SAID SLEEVE UPWARD ONSAID TUBULAR SUPPORT TO REMOVE THE ENDWISE FORCE AGAINST SAID SEALINGAND ANCHORING ASSEMBLY TO RELEASE THE SAME.